A recent survey conducted by ZOOM and Applied Research & Consulting LLC reported that the events of September 11 have motivated kids to volunteer and that more than 80% volunteer. A disbeliever of this information took his own random sample of 500 kids in an attempt to show that the true percentage of kids who volunteer is less than 80%.

a. Find the p-value if 384 of the surveyed kids said they do community volunteer work.

b. Explain why it is important for the level of significance to be established before the sample results are known.